Bayer Leverkusen will be without Michael Kadlec for several weeks after he suffered a knee ligament tear during their Europa League win against Rapid Vienna on Thursday night.
The Czech Republic international has already made 13 appearances this season for club and country, scoring one goal in Leverkusen's home draw with Monchengladbach.
An MRI scan on Friday revealed the extent of the damage which forced Kadlec to be substituted after just nine minutes.
The news comes as a particular blow to Leverkusen as they travel to Bundesliga leaders Bayern Munich on Sunday.
Information from the Press Association was used in this report.